Distillation system



Feb. 16, 1932. H. LEA

DISTILLATION SYSTEM Filed May 5, 1928 4 sheets-sheet 1 [727222202 Jfenzy1 Led.

Feb. 16, 1932. H. I LEA DI STILLATION SYSTEM Filed May 5, 1928 4Sheets-Sheet 2 17271:): for J/fflIJ I/ I Lea.

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Feb. 16, 1932. H. I LEA DISTILLATION SYSTEM Filed May 5, 1928 4Sheets-Sheet 5 Feb. 16, 1932. H. l. LEA

DISTILLATION SYSTEM Filed May 5,

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a ile/way Patented Feb. 16, 1932 PATENT OFFICE HENRY I. LEA, LOB enema,CALIFORNIA.

DISTILLATION SYSTEM Application flied Mai 5,

The present invention relates generally to distillation systems, stillsand condensers, and more particularly to means for effecting extremelyeconomical distillation; it being understood that the utility of theinvention is in no way limited to the distillation of any one kind ofliquid but is broadly applicable to the distillation of a variety ofliquid substances.

The cost involved in operating the usual types of distillation equipmentis such as to restrict the scope of utility of the equipment andtherefore to limit the variety and amount of products that mightotherwise be produced with more economical distillation means.

For instance, pure water for industrial uses might more commonly andprofitably be obtained from ocean or impure river arid lake waters iffacilities were available for distillation with greater economy than canbe accomplished by usual means, whereas a comparatively limited amountof water, impure water, or no water at all would otherwise be used dueto the expense of distillation. It is therefore a purpose of thisinvention to provide such economical distillation facilities.

By the use of the present distillation apparatus, as hereinafterdescribed, distillation may be accomplished economically due to the factthat heat once put into the system is retained and recycled within thesystem so as to continuously vaporize the feed liquid without thefurther addition of heat over that required to satisfy the heat lossesfrom the apparatus and to re lace that removed from the system as sensi1e heat in the distillate and residue. The apparatus is unitary andcompact in construction and may be made in comparatively small sizes,suitable for domestic distillation of water for instance, or it may bebuilt in comparatively large unit sizes for ordinary commercial andindustrial use, and in battery form for large scale operations-such asspecial industries, or more generally, irrigation works and city supply.

The various advantages and features of the invention, including thosementioned hcreinahove and others of importance, will be more fullyunderstood from the following de- 1928. Serial No. 275,437.

tailed description of typical embodiments of the invention throughoutwhich reference is made to the accompanying drawings, in which:

Figure 1 is a longitudinal medial section of a unit embod ing myinvention, certain elements being i lustrated diagrammatically;

Fig. 2 is a longitudinally contracted view of Fi 1, the parts beingshown on an enlar cc? scale;

ig. 3 is a section on line 33 of Fig. 2;

Fig. 4 is a section on line 4-4 of Fig. 2;

Figs. 5 and 6 are similar to Fig. 2, but show variational forms ofcondensers.

Fig. 7 illustrates a battery installation of units;

Fig. 8 is a fragmentary section on line 8-8 of Fig. 7, but showingcertain provisions for;i removing a unit part from the battery; an

Fig. 9 is a view similar to Fig. 2 but showing, conventionally, meansfor pressure regulation.

It will be understood at this point that the purpose of the drawings andthe following description is to set forth the invention clearly,irrespective of certain features of construction that may be alteredwithout departure from the spirit of the invention.

Referring to the drawings, a distillation unit is generally illustratedat U. The unit is seen to embody a vertical cylindrical condenser shell10 having a bottom end closure 11 fixed thereto, as at 12, and an up erend closure 13 removably fitted to the she l at 14. Extending within theshell and annularly spaced therefrom is a. cylindrical tube 15 which, inconjunction with the outer shell end closures 11, 16 and 13 forms acondenser. Although the condenser may be of various forms, as later willbe made apparent, the type illustrated in Figs. 1 and 2 will bedescribed as a tvpical embodiment for a distillation unit U.

The condenser tube 15 is joined to the shell I through engagement withthe outer shell as at 10a. The ring plate is provided with equallyspaced apertures 16b around its outer periphery, and is threaded on itsinner periphcry 16a to receive cover plate 17. It is seen that shell 10and condenser tube 15 define an annular compartment C which opensupwardly through apertures 16?) into the space between the upper endclosures of the condenser tube and outer shell. A tube or weir 18,threaded throughout its length, is screwed into a central opening 17a inthe cover plate 17 and thus may be adjusted vertically by screwing ineither direction. Handles or lugs 80 are provided on the cover in orderthat for purposes which will later be disclosed, the cover and weir 18may be removed from the condenser tube after screwing the cover from itsseat on plate 16. A liquid feed line 19 containing valve 190 extendsthrough shell 10 at 19a, the purpose of this line being to admit liquidto the lowermost portion of compartment C.

Extending through the interior of the condenser tube, which interior Iterm an evaporating chamber V, is an evaporator generally indicated atE, annularly spaced from the condenser tube 15, as at S. It isunderstood that any suitable form of evaporating means may be used, butthat the type described hereinafter is a preferred form which has beenfound to be satisfactory for the present purposes.

Embodied in the evaporator E is a heater tube 20 extending through theouter shell bottom at 21, within and annularly spaced from weir 18 as atA, and through the upper closure 13 at 21a. The heater tube is supportedvertically by means of lock nuts 31 and 31a hearing against the upperand lower surfaces, respectively, of plate 11. Although heat supplymeans of anysuitable nature may be contained within tube 20, I haveprovided, for this purpose, an electric heating element 22 wh ch extendsthrough the tube and around which any suitable material may be packedfor conducting heat from the element to the tube wall. It is understoodthat tube 20, in effect, may constitute the sheath for an electricheating element; that is, the same tube that supports the cups may bethe only metal wall between the source of heat and the liquid. A sectionof high resistance wire 22a is included in the heating element, thissection comprising substantially the heating length of the element andextending downward from an upper part of tube 20 a distance inaccordance with the extent of heating surface desired. Instead of usinga heating element having a single high resistance or heating portion as22a, it may be desirable to have a series of such portions joined end toend, the members of the series having varied resistances so as toprovide for varied heating temperatures within the extent of the heatingelement. In other words, the heat ing element-the source of heat-mayextend throughout the length of the heating tube, or only a portion ofits length; and it may be so arranged as to give different effectivetemperatures at different portions of its length. I have here shown theheating elenient extending only a part-length of the tube in order todescribe certain actions that take place when the lower part of the tubeis not directly heated. The extremities 22b of the heating element,preferably of low resistance wire, extend through caps 23 and may beconnected to any suitable source of current.

Mounted on heater tube 20 is a plurality of vertically spaced liquidreceiving on s 24, joined to the tube as at 25, and provide withoverflow pipes 26. It is evident that liquid discharged into uppermostcup 24a through weir 18, overflows through pipe 260, into cup 2415, thenflows laterally across that cup and around sheath 20, and continuesdownward, similarly through the successive cups, to cup 240. Liquid incup 240 is discharged through outlet pipe 27, which passes through plate11, leakage being prevented by lock-nut 280: (with packing) which isthreaded onto pipe 27. Cup 240 rests at 29 on support 29a, shapedsimilarly to the side wall of the cup and recessed into plate 11 at 30to form a water-tight joint, the purpose of this joint being to preventliquid in the bottom of the evaporating chamber, around the support,from coming in contact with tube 20 when heat is su plied to the latterwithin its lower extent. X liquid outlet pipe 32 threaded into plate 11at 33, serves to remove liquid from chamber V as will be hereinafterdescribed.

When it is desired to remove the evaporator E from the apparatus, caps23 lock nuts 31a, and 21a are removed from the heater tube, lock nut 28ascrewed from pipe 27, upper shell closure 13 moved to one side, cover 17with weir 18 removed from plate 16 as previously described, and theevaporator lifted upwardly through the top of the condenser.

I will now describe generally the operation of unit U. It is assumedthat heater tube 20 is brought to a suitable evaporating temperaturethroughout its heating length corresponding to the reistance wire extent22a of heating element 22. Raw feed liquid from which distillate is tohe produced is fed into compartment C through line 19, the amount of Howbeing regulated by valve 190. The feed liquid flows upward, filling theannular space between the condenser tube 15 and shell 10, throughapertures 16?), and overflows downward through the annular space A andin contact with heater tube 20 into uppermost cup 24a. The condensertube preferably is sutiiciently close to shell 10 in order that theliquid may flow with fairly high velocity and thus provide for efficienttransfer of heat from the condenser tube 15 to the liquid. Due tovaporizatlon within evaporating chamber E simultaneously with the feedliquid flow along the outer condenser surface, the feed temperature israised as the liquid flows upward in compartment C due to its receivingheat which passes through the condenser wall from sources within thechamber as will be described later.

The feed liquid temperature is preferably raised to or near the boilingpoint of that portion of the liquid to be vaporized, by the time thefeed reaches the upper edge of weir 18. In flowing downward throughspace A and in contact with tube 20, a portion of the feed may bevaporized, in which event the liquid flows into cup 24a and the vaporflows outwardly into the uppermost part of evaporating chamber E andcondenses either on tube 15 or plates 16 and 17. A portion of the liquidin the cup is then vaporized due to its contact with hot tube 20 orportions of the cup receiving heat from the heater tube. Similarly,vaporization of the liquid continues as the liquid flows downwardlythrough those cups contained within the extent of heating element 22a.The liberated vapor condenses on the inner surface of condenser tube 15and in so doing, gives up its heat of condensation which then passesthrough the tube wall and is taken up as sensible heat in the feed.

Additional transfer of heat from tube 20 to the condenser wall iseffected in that heatfrom the portions T of the tube between the liquidlevel in the cups and the adjacent cup bottoms may serve to superheatthe gases in chamber E, the superheat in turn being given up to thecondenser tube, or it may be radiated directly to the condenser tube. Itis by this feature of the invention that sufficient heat may betransferred from the heating element to the feed liquid outside thecondenser tube wall to give the feed liquid a portion of its latent heatof vaporization before it enters the vaporizing chamber. For instance,assuming'that heat transfer from the heating tube to the condenser tubeoc curred only through the medium of vapor exactly at its temperature ofvaporization from the liquid phase, the temperature of feed liquid ofsimilar composition obviously could be raised only to its boilingtemperature by the transfer of heat of condensation of the vapor throughthe condenser tube wall. Further transfer of heat beyond this-pointwould not occur due to equalization of temperaturcs of the feed andvapor inside the condenser tube, and therefore the feed would notreceive any of the latent heat necessary for vaporization. However bythe transfer of heat from the bare portons T of the heat ing tube, ashereinabove described, latent heat of vaporization may be transferred tothe feed before actually entering the vaporizing chamber.

Residual liquid flows downwardly throu h the cups below the heatingelement 22a wit 1- out further addition of heat. Due to thoroughexposure of the liquid in so doing, by virtue of the large evaporationsurface in the cups, the liquid may be cooled either by furthervaporization at the expense of sensible heat of the liquid or by contactwith gases which have been cooled through contact with the condensertube. The cooled residual liquid or concentrate is discharged throughpipe 27 Condensate formed on the condenser inner wall flows downwardlyin a thin film so that when it arrives at the base of the condenser tubeit has given up most of its heat to the feed liquid and is cooled to atemperature near that of the inflowing feed. The distillate isdischarged through pipe 32. The sizes of pipes 27 and 32 may be selectedso that the outflowing liquid creates a suction which is effective inremoving uncondensed gases from chamber E.

Bearing in mind the foregoing description of structure and operation ofone specific and illustrative form of the invention, it can now bepointed out that, in a broad sense, the operation embodies thevaporization of the liquid during its flow along a suitable heatingelement and within and surrounded by a condenser wherein the coolingmedium is the feed liquid that is constantly flowing to the evaporator.The evaporator may be viewed as being heat insulated by the surroundingcondenser, which arrangement prevents or minimizes heat losses andnecessitates the transfer into the feed liquid of sub tantially all thelatent heat given up on condensation of the vapor. Due to thesearrangements the heat losses from the apparatus are relatively smalland, of course, may be kept down by proper insulation and in general arelower just in proportion as the temperature of the feed liquid in thecondenser is kept low. However, the temperature to which the feed liquidshall be heated in the condenser depends also upon other considerationsof operation. It will readily be seen that the total heat taken from thesystem is comprised of heat losses from the apparatus plus the sensibleheat in the discharged distillate and residue. Generally speaking theamount of heat in the discharged distillate is a quantity depending uponthe volume of distillate and its temperature, and is also a quantitydependent upon the amount of heat given up to the feed liquid in thecondenser. Again the heat content of the feed liquid in the condenser,taken up in given quantity of heat from the distillate. depends againupon the amount of feed and upon the proportion of the total feed whichis vaporized within the chamber; and the .final temperature of theresidue is a. matter depending upon the rate of residue flow through theapparatus, upon the temperatures reached in the lower part of theapparatus around the heatcrtube, and is 5 therefore dependent upon thetemperatures of the distillate in the lower part of the apparatus andupon the amount of heat which may be thrown off from the residue byevaporization during its downward flow after leaving the directly heatedzone. If in any case the sensible heat of the residue is large, it maybe desirable to transfer some of that heat to the feed liquid before'itgoes to the condenser; but whether this is to be done in any given caseinvolves also a consideration of the condensing efliciency of the soheated feed liquid, and also a consideration of the fact that a coolerfeed liquid in the condenser does in fact take more heat from theresidue during its travel through the lower parts of the apparatus.

For different purposes, dependent upon whether and how the sensible heatof the distillate or residue may be subsequently utilized, the apparatusmay be operated at various rates of heat supply and of various rates offeed; and proportions of vaporization; but in general it IS usuallydesirable, by proper proportioning of the parts of the apparatus toobtain the maximum heat transfer and by proper control of the feed rateand the proportion of the feed vaporized, to cause the temperatures ofthe discharged liquids, both distillate and residue, to approach asclosely as possible to the feed temperature, with the resulting low netloss of heat. And since the heat put into the system need but equal thattaken from the system, it is evident that comparatively little heat,considering that theoretically required for vaporization, need besupplied through the heating element. In the final analysis this lowheat requirement is essentially due to the arrangement which greatlyminimizes heat losses and to arrangements which provide forevaporization without any material loss of heat.

In order to carry out the operations that have now been described, theessential features of the apparatus may be viewed as comprising thecentral or interior heating and vaporizing arrangement surrounded, andpreferably closely surrounded, by a condensmg arrangement; means beingprovided to cause the unvaporized liquid to flow along preferably inclose or good heat transfer relation or contact with the heater andvaporizer, keeping the unvaporized liquid around the heater andvaporizer until it is vaporized to the des red extent, and allowing thegenerated vapor then immediately to come into contact with, and to beimmediate 1y surrounded by, the condenser. Generally speaking, anysuitable means for keeping the unvaporized liquid in proper relation or5 contact with the central heater may be utilized; and the arrangementof cups here illustrated is to be taken as but one specific illustrationof a means that not only keeps the unvaporized liquid flowing closelyaround the heater, but also gives it a 00d and wide expanse ofvaporization sur ace while keeping it in constant and fairl rapidmotion, thus preventing deposit of se iment even when unvaporized liquidreaches high degree of saturation, with respect to substances carried insolution. Thus, although the described arrangement is at presentpreferred, other arrangements, which will accom lish the same generalpurposes, may be use and in any case, as will of course be obvious, theexternal configuration of the heater tube and its connective parts mayle made of such form as to increase the surface f heat conduction, if sodesired.

The apparatus, even in the simple form as described, is capable ofmodification to vary greatly the ratio of evaporating surface tocondensing surface, without an change in general desi or construction.hVithout detailed description it will be seen how these ratios may bevaried by changing the relative dimensions of the cup diameters, theirspacings, and the diameter of the condenser tube; and thesemodifications, together with the control of liquid and heat supplypreviously spoken of, give the device a very wide range of efi'ectiveoperation.

And as regards the arrangement of the condenser, other specificstructures may be utilized, just so long as the condenser with its feedliquid surrounds or substantially surrounds, or is in immediate contactwith substantiall the whole of the body of vapor that surroun s theinterior eva orator.

Thus in Fi ures 5 and 6 have illustrated types of con ensers which maybe used in place of the relatively simple type of Fig. 1, but which havethe same general spacial arrangement with respect to the evaporator E.

It is obvious that these and other similar types of condensers. bysuitable proportioning of parts thereof, may provide increasedcondensing surface over that of the relatively simplified form ofcondenser previously described. The unit shown in Figure 5 is seen toembody an outer condenser shell 10, an upper closure 13, and anevaporator E, similar to those portions of Fig. 1. Plate 11?), joined tothe shell as at 63 serves as a bottom end closure for evaporatingchamber V, also as a tube sheet and as support for ring ehannel 60 whichis remova ly fixed to plate 111) as at 61. A plurality of condensertubes 15?) are expanded at their lower ends into the bottom plate as at62 and are similarly expanded at their upper ends into ring plate 165,which is generally similar to plate 16 of Fig. 2 exeept that it iscircular throughout its outer periphery and carries a gasket 67 on its139 outer edge for engagement with shell 10, as

at 106, to make a water tight joint between the shell and ring plate.Thus plate 16b,

in addition to serving as a carrier for cover 6 17, serves as a floatingtube sheet for movement within the shell as tubes 15b expand orcontract. Condensate formed in chamber V may be drained therefromthrough a line 32a extending through shell 10 as at 33a. The operationof this unit is similar to that of Fig. 1. Feed liquid, admitted to thering channel interior 60a through line 19, flows upward throughcondenser tubes 15b into space 68 and thence downward throu h weir 18 asheretofore explained. The fee liquid containing compartment C1 whichcomprises the chamber 60a, the interior of tubes 15?) and chamber 68, isobviously similar, in effeet, to chamber C of Figure 1.

Figure 6 is generally similar to Figure 1 except that condenser tube 15of the latter is replaced by tubular condenser coil 15c, and ring plate160 is provided with asket 67 around its outer periphery as descri ed inthe preceding paragraph. Bottom plate 70 is removably connected to shell10 as at 65. Condenser coil 150 extends within evaporating chamber V andis joined to feed inlet line 19 by union 66, and at its upper extremityextends throu h plate 160 and into chamber 68a as at 71. eed liquidflowing through line 19 passes upwardly through a coil 15c and intochamber 68a. The feed liquid containing compartment C2 in this instancecomprises the space inside the tube coil and chamber 68a.

In Fig. 7 I have illustrated a battery embodiment of my invention havingoperating characteristics similar to those of a sin le unit butproviding for increased capacityiy the use of a number of units within asingle outside shell. In the battery, an outer shell 100, having bottomclosure 11a and top closure 13b containing removable covers 13a,encloses a plurality of units 15 s aced from the shell and from eachother to orm liquid receiving compartment 0. The purpose of thiscompartment is similar to that of compartment O of the single unit. Feedliquid inlet pipes 81 extend through bottom 11a and are spaced betweenthe units U to effect even distribution of the feed within the shell inorder that at any height H in the path of the upward flowing feed, theliquid temperatures between the various units will be substantially eual. To compensate for possible inequalities in the heights of weirs180;, which inequalities would result in unequal flows of feed li uid tothe separate evaporators, valves genera ly indicated at 35 are providedfor regulating the amount of liquid which flows over the weirs into theevaporators. Each valve is comprised of a tubular stem 36 threaded aboutsheath 20 and extending through packing gland 37, handles 38, fastenedon the stem, and tapered valve closure 36a, integral with the stem, forengagement in weir 18a. Leads 226 from the heating elements are seen tobe connected to current supply lines 220.

Distillate and residue flowing through lines 32a and 27a are dischargedinto receivers 40a and 40, respectively, which may lead to suitabledistillate and residue containers. Bottom condenser tube closures 41,similar to plate 11 of Fig. 2, are joined to shell bottom 11a by screws42 as shown. The general arrangement of parts at the base of each unitis similar to those of the previousl described unit. Insulation 47 isrovide for minimizing heat losses from t e battery.

When it is desired to remove an evaporator E from the battery, leads 226are disconnected from lines 220, handle 38 is removed from stem 36,cover 130; moved to one side and a cylindrical shell 43, tapered at itslower and 43a lowered through the opening 136 to seat on plate 16 asillustrated in Figure 8. The latter is provided with raised bevelsurface 44 for engagement with and 43a at shell 43 to form a water tight'oint which prevents liquid in compartment d from flowing over the uppercondenser closure. After removing cap 23, lock nut 28a, and lock nut 31afrom the bottom of the heater tube 20, cover plate 17 may be screwedfrom its seat and with the evaporator lifted from the battery.

In Fig. 9 I have shown, conventionally, means for controlling pressurewithin unit U, although it is understood that any suitable pressurecontrol means may be used. Lines 32 and 27 extend to distillate andresidue receiving tanks 53 and 52, having drain valves 56. Line 54extends from upper portions of the tanks to pump 55 as shown. Undernormal conditions of distillation at atmospheric pressure, the unitoperates as heretofore described with pressure release valve 58 open tothe atmosphere. If it is desired to operate at pressures aboveatmospheric, valve 58 may be adjusted accordingly, pressure within theapparatus built up by vaporization within chamber E, and the liquid intanks 52 and 53 intermittently drained through valves 56. For operationunder vacuum, valve 58 is closed, and pressure within the apparatusreduced by pump 55. Liquid in the tanks is maintained at sufficientheight so that liquid pressure on the bottoms of the tanks is e uivalentto the atmospheric pressure, an any liquid in excess of that required tomaintain that height may be drained through valves 56. The feed pressurein line 19 is in all instances, regulated according to the distillationpressure.

Certain salient features of the invention are recognized from the abovedescription, irrespective of relatively detailed characteristics ofembodiments described therein. Thus it is seen that by substantiallysurrounding an evaporating means by condensing means, provision is madefor a distillation system of highest thermal efliciency, as set forthhereinabove in considering its theorectical aspects. More explicity, byproviding evaporating means of the general character described,efiieient transfer of heat from the heating means to the raw liquid iseffected, and by roviding condensing and cooling means 0 such naturethat said heat contained either in liquid or va or is transferred almostentirely to the cool eed liquid, the efficiency of the system isobviously of high magnitude.

It will be understood the drawings and description are to be consideredmerely as illustrative of and not restrictive on the broader claimsappended hereto, for various changes in design, structure andarrangement may be made without departing from the spirit and scope ofsaid claims.

I claim:

1. A distillation apparatus embodying a liquid carrying condenser havinga wall which is in liquid contact at one surface and immediatelysurrounds a vapor chamber at its opposite surface, an evaporating meansin the va or chamber, means for directing liquid rom the condenser intothe vapor chamber and to the evaporating means, and means for removingcondensate from the lower part of the vapor chamber.

2. A distillation apparatus embodying a liquid carrying condenser havinga wall which is in liquid contact at one surface and immediatelysurrounds a vapor chamber at its opposite surface, an evaporating meansin the vapor chamber, means for directin liquid from the condenser intothe vapor c amber and to the evaporating means, means for directing suchliquid in a flow around and in heat transferring contact with theevaporating means, and means for removing condeniate from the lower partof the vapor cham- 3. In a distillation apparatus, an outer shellenclosing a vertically disposed condenser tube and spaced therefrom toform a liquid containing compartment, end closures for the tube,evaporating means within the condenser tube and annularly spacedtherefrom, and valve controlled means in the upper end tube closure fordirecting the flow of liquid from said compartment to the evaporatingmeans.

4. In a distillation apparatus, a li uid carrying condenser in avertically exten ing tubular formation defining an inner vapor chamber,one wall of the condensercontacting liquid on one side and vapor on theother, a heater tube extending vertically and centrally within the vaporchamber, means to feed liquid to be distilled into the lower end of thecondenser, means 'to direct liquid from the upper end of the condenserto the upper end of the heater tube, means to direct flow of liquiddownwardly around the heater tube out of contact with the condenser,said means comprising a series of vertically spaced cups surrounding thetube, and overflow means directing liquid from one cup to a cup nextbelow, and means to take off condensate at the bottom of the vaporchamber out of contact with the heating tube.

5. In a distillation apparatus, an outer shell enclosing a verticallydisposed condenser tube and spaced therefrom to form a liquid containingcompartment, a vaporizing chamber within the condenser, an evaporatorwithin the chamber and spaced from the condenser, valve means foradmitting raw liquid to the lower end of said compartment, valve meansfor admitting heated raw liquid from the upper end of the compartment tothe evaporator, and means for separately discharging distillate andresidue from said chamber.

6. In a distillation apparatus, a vertically extending condenser intubular formation embodying annularly spaced inner and outer walls, theinner wall definin an inner vapor chamber, an evaporator wit in thechamber and spaced from said inner wall, means for admitting raw liquidto the base of the annular space between the condenser walls, means todirect liquid from the upper end of said space to the evaporator, meansfor separately discharging distillate and residue from said chamber, andmeans for controlling the pressure in the chamber.

7. In a distillation apparatus, an outer shell, a plurality ofvertically disposed condenser tubes within the outer shell horizontallys aced therefrom and from each other to define a common liquid receivingcompartment, each condenser tube enclosing an evaporating chamber,separate evaporating means within each condenser tube, annularly spacedtherefrom and extendin through the outer shell, means for feeding liquidinto the base of the common compartment, and means for selectivelycontrolling flow of liquid from the compartment into the severalevaporating chambers. 1

8. A distillation apparatus, embodying a heater tube, means to directflow of liquid about the tube in contact with a portion of it only, sothat a remaining portion of the tube may be in direct contact withvapors arising from the liquid, walls forming a liqaid-carryingcondenser in hollow formation and arranged in direct heat transfercontact with such vapors, and means for directing feed liquid throughthe condenser and to the heater tube.

9. In a distillation apparatus, a vertically extending condenser intubular formation embodying annularly spaced inner and outer walls, theinner wall defining an inner vapor chamber, a heating means extendingvertically and centrally within the vapor chamher and spaced from saidinner wall, means to introduce liquid to be distilled to the base of theannular space between the condenser walls, means to direct liquid fromthe upper end of said annular space to the upper end of the heatingmeans, means to direct liquid flow downwardly in contact with theheating means and out of contact with the inner condenser wall, andmeansfor taking ofl condensate within the vapor chamber from the bottomof the inner condenser wall.

10. In a distillation apparatus, walls forming a vertically disposedc'ondenser in a tubular formation which surrounds an inner vaporchamber, a heater within the upper interior of said chamber and spacedfrom the chamber walls, means for supplying liquid to said heater, meanswithin the condenser and below said heater for causing extended surfaceexposure of liquid heated by the heater, and means for separatelydischarging distillate and residue from said chamber.

11. In a distillation apparatus, Walls forming a vertically disposedliquid carrying condenser in a tubular formation which surrounds aninner vapor chamber, a heater within the upper interior of said chamberand spaced from the chamber walls, means for discharging liquid from theupper portion of said condenser to the heater, means within thecondenser and below said heater for causing extended surface exposure ofliquid heated by the heater, and means for separately dischargingdistillate and residue from said chamber.

12. In a distillation apparatus, a vertically extending condenser intubular formation em bodying annularly spaced inner and outer walls, theinner wall defining an inner vapor chamber, a heater tube extendindownwardly within said chamber from the upper end thereof and spacedfrom said inner condenser wall, means to feed liquid to be distilled tothe base of the annular space between the condenser walls, means todirect liquid from the upper end of said space to the upper end of theheater tube, heat supplying means within the tubc and extendingdownwardly only a part way through said chamber, means on the heatertube below said heat supply means for causing extended surface exposureof heated liquid, and means for separately discharging distillate andresidue from said chamber.

13. In a distillation apparatus, a common outer shell, a plurality ofvertically disposed condenser tubes within the common outer shell, saidtubes being horizontally spaced from the shell and from each other todefine a common liquid receiving compartment, within the outer shell andsurrounding the several tubes, each condenser tube enclosing anevaporating chamber, separate evapo rating means within each condensertube and :innulzirlv spaced therefrom, means for f eding liquid into thebase of the common compertinent, means for directing and selectivelycontrolling flow of liquid from the upper part of the compartment to theupper ends of the evaporating means in the several evaporating chambers,and means for separately discharging residue and condensate from thelower ends of each of the several evaporating chambers.

14. A distillation apparatus embodying, walls forming a liquid carryingcondenser in a tubular formation which surrounds an inner evaporatingchamber, heating means in the evaporating chamber and spaced from thechamber wall means for feeding liquid to the condenser, means fordirecting liquid from the condenser to one end of the heating means, andmeans to direct the flow of liquid along the heating means and in directcontact with a portion of its heating surface only, whereby vaporsevolved from heated liquid may come into direct contactwith theremaining portion of the heating surface for superheating.

15. The method of distilling a liquid, that includes, generating andmaintaining a body of vapor by passing liquid over a heater and in heattransferring relation to the body of vapor, maintaining a liquid feedthrough a zone surrounding the heater, said liquid feed thereby takingup the heat of condensation of the vapors, and superheating the vaporsat said heater to cause the heat of superheat to be transferred to thefeed.

16. In a distillation apparatus, a structure defining an elongated vaporspace, an evaporator within said structure and adjacent said vaporspace, a condenser included within said structure and having a heattransfer wall in direct exposure to vapors in said vapor space, meansfor feeding liquid through said condenser wherein the liquid ispreheated, means for conducting the preheated liquid from said condenserover said evaporator, the liquid being vaporized in passing over theevaporator, and the vapors being liberated into said vapor space andcondensed on the wall of said condenser, means for drawing off theunvaporized residue from said evaporator, and means for separatelydrawing off the condensate.

17. In a distillation apparatus, a structure defining an elongated vaporspace, an elongated evaporator within said structure and adjacent saidvapor space, :1 condenser included within said structure and having aheat transfer wall in direct exposuic to vapors in said vapor space,said condenser being spaced from the evaporator and extendingsubstantially parallel therewith, means to feed liquid to be distilledinto one end of the condenser, means to direct the liquid from the.other end of the condenser to one end of the evaporati'ir, the liquidthen being vaporized in passing longitudinally over said evaporator in arcrcisc direction to its path through the condenser, and the vaporsbeing liberated into said vapor space and condensed on the wall of saidcondenser, means for drawing off the unvaporized residue from saidevaporator, and means for separately drawing off the condensate.

18. In a distillation apparatus, a structure defining an elongated vaporspace, an elongated evaporator within said structure and adjacent saidvapor space, means for supplying heat to a part length onl of saidevaporator, a condenser include Within said structure and having a heattransfer wall in direct exposure to said vapor space, said condenserbeing spaced from the evaporator and extending substantially paralleltherewith, means to feed liquid to be distilled into one end of thecondenser, means to direct the liquid from the other end of thecondenser to one end of the evaporator, the liquid then being vaporizedin passing lon 'tudinally over said evaporator in a reverse irectio n toits path through the condenser, and the vapors being liberated into saidvapor space and condensed on the wall of said condenser, means fordrawing off the unvaporized residue from said evaporator, and means forseparately drawing otl the condensate.

l9. Distillation apparatus comprising, a

shell, a liquid carrying condenser in tubular formation Within saidshell and defining an inner vapor space, said condenser comprising aplurality of liquidcarrying tubes arranged about said vapor space, anevaporator extending longitudinally and centrally through the vaporspace, means to feed liquid to be distilled to the condenser, means todirect the liquid from one end of the condenser to one end of saidevaporator, means to direct the liquid longitudinally over theevaporator to its opposite end, and means for supplying heat to saidevaporator.

In witness that I claim the foregoing I have hereunto subscribed my namethis 20th day of April, 1928.

HENRY I. LEA.

extending substantially parallel therewith,

means to feed liquid to be distilled into one end of the condenser,means to direct the liquid from the other end of the condenser to oneend of the evaporator, the liquid then being vaporized in passinglongitudinally over said evaporator in a reverse direction to its paththrough the condenser, and the vapors being liberated into said vaporspace and condensed on the wall of said condenser,

means fordrawing off the unvaporized residue from said evaporator, andmeans for separately drawing off the condensate.

l9. Distillation apparatus comprising, a shell, :1 liquid carryingcondenser in tubular 3o formation Within said shell and defining aninner vapor space, said condenser comprising a plurality ofliquidcarrying tubes arranged about said vapor space, an evaporatorextending longitudinally and centrally through the vapor space, means tofeed liquid to be distilled to the condenser, means to direct the liquidfrom one end of the condenser to one end of said evaporator, means todirect the liquid longitudinally over the evaporator to its oppositeend, and means for supplying heat to said evaporator.

In witness that I claim the foregoing I have hereunto subscribed my namethis 20th day of April, 1928.

HENRY I. LEA.

CERTIFICATE OF CORRECTION.

Patent No. 1,845,159. Granted February 16, 1932, to

HENRY I. LEA.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 7,lines to 92, claim 15, strike out the words "and in heat transferringrelation to the body of vapor" and insert the same after the word"heater" in line 93, of same claim; and that the said Letters Patentshould be read with this correction therein that the same may conform tothe record of the case in the Patent Office.

Signed and sealed this 12th day of April, A. D. 1932.

M. J. Moore,

(Seal) Acting Commissioner of Patents.

CERTIFICATE OF CORRECTION.

Patent No. 1,845,159. Granted February 16, 1932, to

HENRY I. LEA.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 7,lines 90 to 92, claim 15, strike out the words "and in heat transferringrelation to the body of vapor" and insert the same after the word"heater" in line 93, of same claim; and that the said Letters Patentshould be read with this correction therein that the same may conform tothe record of the case in the Patent Office.

Signed and sealed this 12th day of April, A. D. 1932.

M. J. Moore, (Seal) Acting Commissioner of Patents.

